On the lunar origin of tektites

The experimental facilities and analytical methods of atmosphere entry aerodynamics have been applied to the study of tektites. Hypervelocity ablation experiments in the laboratory have reproduced the same surface sculptures, geometric relationships, systematic stria distortions, and coiled circumferential flanges as those found on tektites from Australia, The aerodynamic evidence demonstrates that the javanites and australites were twice melted, the second time by aerodynamic heating of rigid tektite glass during atmosphere entry. Experiments conducted on molten glass ejected into the atmosphere at various viscosities and velocities show that the primary australites were formed in an environment in which the atmosphere density was many orders of magnitude less than that at the earth's surface; this contradicts the hypothesis of tektite origin from the earth or other atmosphere-shrouded planets. Modern calculation methods for aerodynamic ablation are shown to be in good agreement with various laboratory experiments and with an entry flight experiment. From the amount of ablation, the distortion of striae, and the spacing between ring waves on australites, entry trajectories have been determined. The moon is the only known celestial body of origin compatible with these trajectories. The distribution of chemical elements in tektites, earth crust, meteorites, and other cosmic bodies is compared, and a brief discussion is given of the chemical differentiation of the lunar crust to which the over-all evidence points.